[1-(Anthracen-9-ylmethyl)-1,4,7,10-tetraazacyclododecane]chloridozinc(II) nitrate

The ZnII atom in the complex cation of the title salt has a square-pyramidal coordination environment defined by four nitrogen atoms from cyclen (1,4,7,10-tetraazacyclododecane) in the basal plane and one chlorido ligand in the apical position.

In the title salt, [ZnCl(C 23 H 30 N 4 )]NO 3 , the central Zn II atom of the complex cation is coordinated in a square-pyramidal arrangement by four nitrogen atoms from cyclen (1,4,7,10-tetraazacyclododecane) in the basal plane and one chlorido ligand in the apical position.The anthracene group attached to cyclen contributes to the crystal packing through intermolecular T-shaped � interactions.Additionally, the nitrate anion participates in intermolecular N-H� � �O hydrogen bonds with cyclen.
The crystal structure of the title compound comprises a [Zn(C 23 H 30 N 4 )Cl] + complex cation and a nitrate anion (Fig. 1).The coordination environment around the Zn II atom is slightly distorted square-pyramidal, with the coordination geometry index (Addison et al., 1984), � = (� À �) / 60 � = 0.08, where � [132.23 ( 9) � ] and � [136.98 (8) � ] are the second-largest and largest angles around the central Zn II atom, respectively.A � value of 0 corresponds to an ideal square pyramid, while a value of 1 corresponds to an ideal trigonal bipyramid.The four nitrogen atoms N1, N2, N3, and N4 of cyclen form the basal plane, with the chlorido ligand occupying the apical position.The mean Zn1-N bond length of 2.16 A ˚(Fig. 2) is comparable to that (2.13A ˚) observed in the crystal structure of the salt Zn(C 23 H 30 N 4 )] + -(ClO 4 ) 2À (Ichimaru et al., 2021).The Zn II atom is displaced by 0.8306 (12) A ˚above the mean basal plane toward the apical chlorido ligand.The Zn-Cl bond length of 2.2464 (7) A ˚is comparable to that found in other Zn II -polyamine complexes with chlorido ligands, such as chlorido(1,4,7,11-tetraazacyclotetradecane-N,N 0 ,N 00 ,N 000 )zinc(II) perchlorate [2.2734 (8) A ˚; Lu et al., 1997] or bis [�-chlorido-(1,4,8,11-tetracyclotetra-decane)zinc(II)] tetrachloridozincate(II) hemihydrate [2.288 (5) A ˚; Alcock et al., 1992].The presence of Cl À as a ligand can be deduced from the synthesis conditions (see Synthesis and crystallization).The bromine salt of the ligand was freed by an anion-exchange resin.In this process, hydrochloric acid was employed to regenerate the resin to its chloride anion form, which is the source of Cl À binding to the Zn II atom.
The anthracene group exhibits a slight deviation from planarity, with fold angles of 4.69 (10) � between the A (C2-C7) and B (C1, C2, C7, C8, C9, C14) rings and 2.78 (11) � between the B and C (C9-C14) rings.The torsion angle defined by Zn1-N1-C15-C1 is 170.33 (18) � , positioning the anthracene group away from the macrocyclic ring, thereby preventing repulsive interactions with the Cl atom.In the crystal, nitrate O1 forms intermolecular hydrogen bonds with H2 of the Zn II complex and H3 of a neighboring molecule.The hydrogen-bond distances O1� � �H2 and O1 i � � �H3 are 1.985 and 2.16 A ˚(Table 1).These interactions contribute to the formation of a spiral structure extending parallel to the b axis The coordination polyhedron around Zn1, with displacement ellipsoids drawn at the 50% probability level.Bond angles are depicted in red, whereas bond lengths are shown in black.

Figure 1
The molecular structures of the complex cation and the anion in the title salt with displacement ellipsoids drawn at the 50% probability level.Cbound H atoms are omitted for clarity; the hydrogen bond is represented as a red dotted line.direction of the crystal.Additionally, intermolecular T-shaped � interactions (Jin et al., 2022) occur between the anthracene ring and a neighboring anthracene ring [symmetry code: (ii): À x, 1 2 + y, 1 2 À z] (Fig. 3).The distance between H8 and the centroid (Cg) of the middle ring of the neighboring anthracene ring is 2.96 A ˚, and the angle C8-H8� � �Cg is 152 � .
The title complex was prepared by adding a MeOH solution (1 ml) of Zn(NO 3 ) 2 •6H 2 O (235 mg, 0.8 mmol) to a MeOH solution (5 ml) of N-Ant-cyclen (287 mg, 0.8 mmol).The mixture was heated, with stirring, at 323 K for 2 h and then concentrated.After the resulting residue was dissolved in a MeOH-water mixture (v/v = 1/1; 2 ml each) and filtrated, the filtrate was allowed to stand for 10 days at room temperature to obtain the title salt (286 mg, 84%).

Special details
Geometry.All esds (except the esd in the dihedral angle between two l.s.planes) are estimated using the full covariance matrix.The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry.An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s.planes.

Figure 3 A
Figure 3A schematic drawing of the T-shaped �-� interactions, with displacement ellipsoids drawn at the 50% probability level.Methylene H atoms of cyclen rings and nitrate ions were omitted for clarity; T-shaped �-� interactions are depicted as green dotted lines.

Table 2
Experimental details.
Computer programs: CrysAlis PRO